The use of spring pins is extensive. A spring pin is a small cylinder (usually of metal) of selected length and diameter, slit longitudinally so that it can be circumferentially compressed whereby it may be driven into a slightly smaller cylindrical hole.
Because spring pins are usually small and difficult to manipulate by hand, it has been found expedient to drive the pins into the holes through the use of a specially designed hand tool or semi-automatic machine. One such tool is shown in the patent to Fox U.S. Pat. No. 3,788,537 for Hand-Loaded Pin Chuck.